feat: unlock redis/postgres backend config with assembly guards

src/polygateway/config.py

@@ -105,7 +105,9 @@ class GatewaySettings:
     cache_ttl_s: int | None
     telemetry_backend: str
     telemetry_sqlite_path: str | None
+    telemetry_pg_dsn: str | None
     redis_url: str | None
+    pricing_path: str | None
     structured_max_retries: int
     lease_ttl_s: float
 
@@ -139,6 +141,7 @@ class GatewaySettings:
             **_load_pgw(env),
         )
         _guard_lease(settings)
+        _guard_stall(settings)
         return settings
 
 
@@ -214,12 +217,20 @@ def _load_breaker(
     )
     if concurrency > 0:
         threshold = max(threshold, concurrency * 2)
+    slowest = max(s.timeout_s for s in sources)
+    probe_floor = slowest + 5.0  # CHS container.py:274-275: 最慢调用 + 清理宽限
     probe = _first(env, f"{scope}__BREAKER__PROBE_TTL_S")
     if probe is not None:
         probe_ttl_s = float(_cast(probe[1], "float", probe[0]))
+        # 装配守卫(M2 设计 §3): 探针租约必须撑过一次最慢调用,否则半开探针在途即被接管
+        if probe_ttl_s < probe_floor:
+            raise ValueError(
+                f"probe_ttl_s({probe_ttl_s})须 ≥ 最大源 timeout_s + 5({probe_floor});"
+                f"调大 {probe[0]} 或调小源超时"
+            )
     else:
-        # 派生规则: 探针租约须撑过一次最慢调用,且不短于冷却期
-        probe_ttl_s = max(2 * max(s.timeout_s for s in sources), cooldown_s)
+        # 派生规则: 探针租约须撑过一次最慢调用,且不短于冷却期(第三项保证守卫恒成立)
+        probe_ttl_s = max(2 * slowest, cooldown_s, probe_floor)
     return BreakerConfig(fail_threshold=threshold, cooldown_s=cooldown_s, probe_ttl_s=probe_ttl_s)
 
 
@@ -251,15 +262,15 @@ def _load_pgw(env: Mapping[str, str]) -> dict[str, object]:
     breaker_backend = _load_choice(
         env, "PGW_BREAKER_BACKEND", frozenset({"memory", "redis"}), "memory"
     )
-    if "redis" in (limiter_backend, breaker_backend):
-        raise ValueError("限流/熔断 Redis 后端在 M2 交付;M1 仅支持 memory")
     _, cache_backend = _require(env, "PGW_CACHE_BACKEND")
     _, telemetry_backend = _require(env, "PGW_TELEMETRY_BACKEND")
     if cache_backend not in ("redis", "memory", "none"):
         raise ValueError(f"PGW_CACHE_BACKEND 非法值 {cache_backend!r}")
-    if telemetry_backend not in ("sqlite", "none"):
-        raise ValueError(f"PGW_TELEMETRY_BACKEND 非法值 {telemetry_backend!r}(postgres 在 M2)")
+    if telemetry_backend not in ("sqlite", "postgres", "none"):
+        raise ValueError(f"PGW_TELEMETRY_BACKEND 非法值 {telemetry_backend!r}")
     redis_url = env.get("REDIS_URL") or None
+    if "redis" in (limiter_backend, breaker_backend) and redis_url is None:
+        raise ValueError("缺关键配置: 限流/熔断后端取 redis 需设置 REDIS_URL")
     return {
         "limiter_backend": limiter_backend,
         "breaker_backend": breaker_backend,
@@ -269,12 +280,21 @@ def _load_pgw(env: Mapping[str, str]) -> dict[str, object]:
         "telemetry_sqlite_path": _require(env, "PGW_TELEMETRY_SQLITE_PATH")[1]
         if telemetry_backend == "sqlite"
         else None,
+        "telemetry_pg_dsn": _load_pg_dsn(env) if telemetry_backend == "postgres" else None,
         "redis_url": redis_url,
+        "pricing_path": env.get("PGW_PRICING_PATH") or None,
         "structured_max_retries": _load_structured_retries(env),
         "lease_ttl_s": _load_lease_ttl(env),
     }
 
 
+def _load_pg_dsn(env: Mapping[str, str]) -> str:
+    """读取 Postgres DSN 并剥 SQLAlchemy 风格驱动后缀(asyncpg 不认 `+driver`)。"""
+    _, dsn = _require(env, "PGW_TELEMETRY_PG_DSN")
+    scheme, sep, rest = dsn.partition("://")
+    return f"{scheme.partition('+')[0]}{sep}{rest}"
+
+
 def _load_cache_keys(
     env: Mapping[str, str], cache_backend: str, redis_url: str | None
 ) -> dict[str, object]:
@@ -308,6 +328,16 @@ def _guard_lease(settings: GatewaySettings) -> None:
         )
 
 
+def _guard_stall(settings: GatewaySettings) -> None:
+    """装配守卫: stall 窗口须 ≥ 最慢源 TTFT 上限,防把正常慢首包误判为卡死(ARCH §7.3)。"""
+    ttfts = [s.ttft_timeout_s for s in settings.sources if s.ttft_timeout_s is not None]
+    if ttfts and settings.backpressure.stall_window_s < max(ttfts):
+        raise ValueError(
+            f"stall_window_s({settings.backpressure.stall_window_s})须 ≥ 最大源 "
+            f"ttft_timeout_s({max(ttfts)});调大 BACKPRESSURE__STALL_WINDOW_S 或调小 TTFT"
+        )
+
+
 def _load_lease_ttl(env: Mapping[str, str]) -> float:
     found = _first(env, "PGW_LEASE_TTL_S")
     return float(_cast(found[1], "float", found[0])) if found else _DEFAULT_LEASE_TTL_S